diff options
| author | Mike Snitzer <snitzer@redhat.com> | 2019-02-06 01:07:58 +0300 |
|---|---|---|
| committer | Mike Snitzer <snitzer@redhat.com> | 2019-02-07 01:24:37 +0300 |
| commit | fa8db4948f5224dae33a0e783e7dec682e145f88 (patch) | |
| tree | c71162dd2bd0cfc5e80d5e2b1ca3d72721f4ff48 /drivers/md/dm.c | |
| parent | 645efa84f6c7566ea863ed37a8b3247247f72e02 (diff) | |
| download | linux-fa8db4948f5224dae33a0e783e7dec682e145f88.tar.xz | |
dm: don't use bio_trim() afterall
bio_trim() has an early return, which makes it _not_ idempotent, if the
offset is 0 and the bio's bi_size already matches the requested size.
Prior to DM, all users of bio_trim() were fine with this. But DM has
exposed the fact that bio_trim()'s early return is incompatible with a
cloned bio whose integrity payload must be trimmed via
bio_integrity_trim().
Fix this by reverting DM back to doing the equivalent of bio_trim() but
in an idempotent manner (so bio_integrity_trim is always performed).
Follow-on work is needed to assess what benefit bio_trim()'s early
return is providing to its existing callers.
Reported-by: Milan Broz <gmazyland@gmail.com>
Fixes: 57c36519e4b94 ("dm: fix clone_bio() to trigger blk_recount_segments()")
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Diffstat (limited to 'drivers/md/dm.c')
| -rw-r--r-- | drivers/md/dm.c | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/drivers/md/dm.c b/drivers/md/dm.c index a0972a9301de..515e6af9bed2 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -1336,7 +1336,11 @@ static int clone_bio(struct dm_target_io *tio, struct bio *bio, return r; } - bio_trim(clone, sector - clone->bi_iter.bi_sector, len); + bio_advance(clone, to_bytes(sector - clone->bi_iter.bi_sector)); + clone->bi_iter.bi_size = to_bytes(len); + + if (bio_integrity(bio)) + bio_integrity_trim(clone); return 0; } |